use the given trigonometric identity to set up a u-substitution and then evaluate the indefinite integral: (intergal of) 4cos^2x dx, with the identity cos2x=1-2cos^2x

Question

hartnn · Answer

@mulline  hi :) 
$\huge \color{red}{\text{Welcome to Open Study}}\ddot\smile$

from cos2x=1-2cos^2x 
try to isolate cos^2 x.

anonymous · Answer

Thanks I totally get it now!

hartnn · Answer

ohh, good :)

anonymous · Answer

can you help me with this one

hartnn · Answer

yeah, you can use, $a^2-b^2 = (a+b)(a-b)$
here, a = cos^2x , b = sin^2 x

hartnn · Answer

and use the fact that : $\sin^2x+\cos^2x=1$

anonymous · Answer

youre a genius.

hartnn · Answer

not actually :P 
math identities are genius :)